Clinical impact of RT-PCR for pediatric acute respiratory infections: a controlled clinical trial

Antibiotic Use and Respiratory Viral PCR Testing Among Pediatric Patients With Nosocomial Fever

Objective Pediatric patients admitted to the hospital often develop fevers during their inpatient stay, and many children are empirically started on antibiotics. The utility of respiratory viral panel (RVP) polymerase chain reaction (PCR) testing in the evaluation of nosocomial fevers in admitted patients is unclear. We sought to evaluate whether RVP testing is associated with the use of antibiotics among inpatient pediatric patients. Patients and methods We conducted a retrospective chart review of children admitted from November 2015 to June 2018. We included all patients who developed fever 48 hours or more after admission to the hospital and who were not already receiving treatment for a presumed infection (on antibiotics). Results Among 671 patients, there were 833 inpatient febrile episodes. The mean age of children was 6.3 years old, and 57.1% were boys. Out of 99 RVP samples analyzed, 22 were positive (22.2%). Antibiotics were started in 27.8% while 33.5% of patients were already on antibiotics. On multivariate logistic regression, having an RVP sent was significantly associated with increased initiation of antibiotics (aOR 95% CI 1.18-14.18, p=0.03). Furthermore, those with a positive RVP had a shorter course of antibiotics compared to those with a negative RVP (mean 6.8 vs 11.3 days, p=0.019). Conclusions Children with positive RVP had decreased antibiotic exposure compared to those with negative RVP results. RVP testing may be used to promote antibiotic stewardship among hospitalized children.

Use and Cost Analysis of Comprehensive Respiratory Panel Testing in a Pediatric Emergency Department

OBJECTIVES

Fever and respiratory infections are among the leading causes of pediatric emergency department visits and hospitalizations. Although typically self-resolving, clinicians may perform diagnostic tests to determine microbial etiologies of these illnesses. Although comprehensive respiratory viral panels can quickly identify causative organisms, cost to the hospital and patient may be significant. The objective of this study was to analyze the financial impact of comprehensive respiratory viral panel use in relation to associated clinical outcomes.

METHODS

This study was a single-center, retrospective chart review of pediatric emergency department patients who were evaluated between October 1, 2016, and April 30, 2018, with International Classification of Diseases, Tenth Revision (ICD-10) code diagnoses of acute upper respiratory infection, fever unspecified, and/or bronchiolitis. Our primary outcome was the effect of comprehensive respiratory viral panel testing and results on the total health care charge to patients. Secondary outcomes were the effect of comprehensive respiratory viral panel testing and results on emergency department length of stay and antimicrobial use.

RESULTS

A total of 5766 visits were included for primary analysis, with 229 (4%) undergoing comprehensive respiratory viral panel testing. Of these, 163 had a positive result (71%) for at least 1 organism. The total cost was significantly higher in the group that underwent comprehensive respiratory viral panel testing ($643.39 [$534.18-$741.15] vs $295.15 [$249.72-$353.92]; P < 0.001). There was no decrease in emergency department length of stay or significant change in antimicrobial use associated with comprehensive respiratory viral panel use.

CONCLUSIONS

This study demonstrates that the utilization of comprehensive respiratory viral panels in pediatric emergency department patients with bronchiolitis, unspecified fever, and/or acute upper respiratory infection adds significant cost to patient care without a decrease in their length of stay or antimicrobial use. Further studies are needed to determine the appropriate targeted use of comprehensive respiratory viral panels.

Point-of-Care and Rapid Tests for the Etiological Diagnosis of Respiratory Tract Infections in Children: A Systematic Review and Meta-Analysis

Fever is one of the most common causes of medical evaluation of children, and early discrimination between viral and bacterial infection is essential to reduce inappropriate prescriptions. This study aims to systematically review the effects of point-of-care tests (POCTs) and rapid tests for respiratory tract infections on changing antibiotic prescription rate, length of stay, duration of therapy, and healthcare costs. Embase, MEDLINE, and Cochrane Library databases were systematically searched. All randomized control trials and non-randomized observational studies meeting inclusion criteria were evaluated using the NIH assessment tool. A meta-analysis was performed to assess the effects of rapid influenza diagnostic tests and film-array respiratory panel implementation on selected outcomes. From a total of 6440 studies, 57 were eligible for the review. The analysis was stratified by setting and POCT/rapid test type. The most frequent POCTs or rapid tests implemented were the Rapid Influenza Diagnostic Test and film-array and for those types of test a separate meta-analysis assessed a significant reduction in antibiotic prescription and an improvement in oseltamivir prescription. Implementing POCTs and rapid tests to discriminate between viral and bacterial infections for respiratory pathogens is valuable for improving appropriate antimicrobial prescriptions. However, more studies are needed to assess these findings in pediatric settings.

Respiratory virus testing and clinical outcomes among children hospitalized with pneumonia

BACKGROUND

Despite the increased availability of diagnostic tests for respiratory viruses, their clinical utility for children with community-acquired pneumonia (CAP) remains uncertain.

OBJECTIVE

To identify patterns of respiratory virus testing across children's hospitals prior to the COVID-19 pandemic and to determine whether hospital-level rates of viral testing were associated with clinical outcomes.

DESIGN, SETTING, AND PARTICIPANTS

Multicenter retrospective cohort study of children hospitalized for CAP at 19 children's hospitals in the United States from 2010-2019.

MAIN OUTCOMES AND MEASURES

Using a novel method to identify the performance of viral testing, we assessed time trends in the use of viral tests, both overall and stratified by testing method. Adjusted proportions of encounters with viral testing were compared across hospitals and were correlated with length of stay, antibiotic and oseltamivir use, and performance of ancillary laboratory testing.

RESULTS

There were 46,038 hospitalizations for non-severe CAP among children without complex chronic conditions. The proportion with viral testing increased from 38.8% to 44.2% during the study period (p < .001). Molecular testing increased (27.2% to 40.0%, p < .001) and antigen testing decreased (33.2% to 7.8%, p < .001). Hospital-specific adjusted proportions of testing ranged from 10.0% to 83.5% and were not associated with length of stay, antibiotic use, or antiviral use. Hospitals that performed more viral testing did not have lower rates of ancillary laboratory testing.

CONCLUSIONS

Viral testing practices varied widely across children's hospitals and were not associated with clinically important process or outcome measures. Viral testing may not influence clinical management for many children hospitalized with CAP.

Effect of Point-of-Care Testing for Respiratory Pathogens on Antibiotic Use in Children: A Randomized Clinical Trial

IMPORTANCE

Limited data are available on the clinical impact of multiplex polymerase chain reaction (PCR) point-of-care testing for respiratory pathogens in acutely ill children.

OBJECTIVE

To evaluate the effect of multiplex PCR point-of-care testing for respiratory pathogens on antibiotic use in acutely ill children.

DESIGN, SETTING, AND PARTICIPANTS

This unblinded, randomized clinical trial was conducted from May 6, 2019, through March 12, 2020. The participants were followed up until hospitalization or discharge from the emergency department (ED) for primary outcome. The study was conducted at the pediatric ED of Oulu University Hospital, Finland. Eligible study participants were children aged 0 to 17 years with fever and/or any respiratory signs or symptoms. Children with underlying medical conditions were included. The statistical analyses were performed between August 11, 2020, and September 14, 2021.

INTERVENTIONS

The participants were randomly assigned in a 2:1 ratio either to undergo multiplex PCR point-of-care testing (18 respiratory viruses and 3 bacteria with results ready within 70 minutes) upon arrival at the ED or to receive routine care.

MAIN OUTCOMES AND MEASURES

The primary outcome was the proportion of children receiving antibiotic therapy. The secondary outcomes were the numbers of diagnostic tests and radiographic imaging procedures performed and costs.

RESULTS

A total of 1417 children were assessed for eligibility. After exclusions, 1243 children (692 boys [56%]) were randomly allocated to either the intervention (829 children) or control (414 children) group. The mean (SD) age of the participants was 3.0 (3.6) years in the intervention group (median [IQR], 1.7 [0.4-4.1] years) and 3.0 (3.5) years (median [IQR], 1.9 [0.4-4.1] years) in the control group. Multiplex PCR point-of-care testing for respiratory pathogens did not reduce the overall prescribing of antibiotics in the emergency department (226 children [27.3%] in the intervention group vs 118 children [28.5%] in the control group; risk ratio, 0.96; 95% CI, 0.79-1.16). Targeted antibiotic therapy was started in 12 children (1.4%) tested with point-of-care multiplex PCR and 2 children (0.5%) in the control group (risk ratio, 3.0; 95% CI, 0.76-11.9). The numbers of diagnostic tests did not differ between the groups, nor did the costs.

CONCLUSIONS AND RELEVANCE

In this randomized clinical trial, point-of-care testing for respiratory pathogens did not reduce the use of antibiotics at the pediatric ED. Testing for respiratory pathogens appears to have a limited impact on clinical decision-making for acutely ill children.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03932942.

Diagnosis of Multidrug-Resistant Pathogens of Pneumonia

Hospital-acquired pneumonia and ventilator-associated pneumonia that are caused by multidrug resistant (MDR) pathogens represent a common and severe problem with increased mortality. Accurate diagnosis is essential to initiate appropriate antimicrobial therapy promptly while simultaneously avoiding antibiotic overuse and subsequent antibiotic resistance. Here, we discuss the main conventional phenotypic diagnostic tests and the advanced molecular tests that are currently available to diagnose the primary MDR pathogens and the resistance genes causing pneumonia.

Application of Multiplex Polymerase Chain Reaction for Pathogen Identification and Antibiotic Use in Children With Respiratory Infections in a PICU

OBJECTIVES

To compare the pathogen identification rate and use of antibiotics before and after the implementation of multiplex polymerase chain reaction testing in children with respiratory infections in a PICU.

DESIGN

Single-center, pre-post study.

SETTING

PICU of Osaka Women's and Children's Hospital, Osaka, Japan.

PATIENTS

Consecutive children with respiratory infections who were admitted to the PICU between December 2017 and November 2018 (premultiplex polymerase chain reaction period) and between March 2019 and February 2020 (postmultiplex polymerase chain reaction period).

INTERVENTIONS

Conventional rapid antigen tests and bacterial culture tests were performed throughout the study period. Multiplex polymerase chain reaction testing using the FilmArray respiratory panel (BioFire Diagnostics, Salt Lake City, UT) was conducted to detect 17 viruses and three bacterial pathogens. During the postmultiplex polymerase chain reaction period, we did not recommend prescribing antibiotics for stable children, depending on the virus species and laboratory test results.

MEASUREMENTS AND MAIN RESULTS

Ninety-six and 85 children were enrolled during the pre- and postmultiplex polymerase chain reaction periods, respectively. Rapid antigen tests identified pathogens in 22% of the children (n = 21) during the premultiplex polymerase chain reaction period, whereas rapid antigen tests and/or multiplex polymerase chain reaction testing identified pathogens in 67% of the children (n = 57) during the postmultiplex polymerase chain reaction period (p < 0.001). The most commonly identified pathogen using multiplex polymerase chain reaction testing was human rhino/enterovirus. Bacterial pathogens were identified in 50% of the children (n = 48) and 60% of the children (n = 51) during the pre- and postmultiplex polymerase chain reaction periods (p = 0.18). There were no differences in antibiotic use (84% vs 75%; p = 0.14), broad-spectrum antibiotic use (33% vs 34%; p = 0.91), or the duration of antibiotic use within 14 days of admission (6.0 vs 7.0 d; p = 0.45) between the pre- and postmultiplex polymerase chain reaction periods.

CONCLUSIONS

Although the pathogen identification rate, especially for viral pathogens, increased using multiplex polymerase chain reaction testing, antibiotic use did not reduce in children with respiratory infections in the PICU. Definitive identification of bacterial pathogens and implementation of evidence-based antimicrobial stewardship programs employing multiplex polymerase chain reaction testing are warranted.

Bacterial lysate add-on therapy to reduce exacerbations in severe asthma: A double-blind placebo-controlled trial

Background

Asthma exacerbations are frequently induced by respiratory tract infections (RTIs). Bacterial lysates have been described to possess immune‐modulatory effects and reduce RTIs as well as asthma symptoms in children. However, whether bacterial lysates have similar effects in adult asthma patients is unknown.

Aims

To reduce asthma exacerbations by add‐on bacterial lysate therapy in adults with severe asthma and to characterize the clinical and immune‐modulatory effects of this treatment.

Methods

Asthma patients (GINA 4) with ≥2 annual exacerbations in the previous year were included. The intervention regimen consisted of OM‐85/placebo for 10 consecutive days per month for 6 months during two winter seasons. Primary end‐point was the number of severe asthma exacerbations within 18 months. The study was approved by the national and local ethical review board and registered in the Dutch Trial Registry (NL5752). All participants provided written informed consent.

Results

Seventy‐five participants were included (38 OM‐85; 37 placebo). Exacerbation frequencies were not different between the groups after 18 months (incidence rate ratio 1.07, 95%CI [0.68–1.69], p = 0.77). With the use of OM‐85, FEV1% increased by 3.81% (p = 0.04) compared with placebo. Nasopharyngeal swabs taken during RTIs detected a virus less frequently in patients using OM‐85 compared to placebo (30.5% vs. 48.0%, p = 0.02).

In subjects with type 2 inflammation adherent to the protocol (22 OM‐85; 20 placebo), a non‐statistically significant decrease in exacerbations in the OM‐85 group was observed (IRR = 0.71, 95%CI [0.39–1.26], p = 0.25). Immune‐modulatory effects included an increase in several plasma cytokines in the OM‐85 group, especially IL‐10 and interferons. Peripheral blood T‐ and B cell subtyping, including regulatory T cells, did not show differences between the groups.

Conclusion

Although OM‐85 may have immune‐modulatory effects, it did not reduce asthma exacerbations in this heterogeneous severe adult asthma group. Post hoc analysis showed a potential clinical benefit in patients with type 2 inflammation.

Effect of Rapid Respiratory Virus Testing on Antibiotic Prescribing Among Children Presenting to the Emergency Department With Acute Respiratory Illness: A Randomized Clinical Trial

IMPORTANCE

There is high usage of antibiotics in the emergency department (ED) for children with acute respiratory illnesses. Studies have reported decreased antibiotic use among inpatients with rapid respiratory pathogen (RRP) testing.

OBJECTIVE

To determine whether RRP testing leads to decreased antibiotic use and health care use among children with influenzalike illness (ILI) in an ED.

DESIGN, SETTING, AND PARTICIPANTS

A randomized clinical trial among children aged 1 month to 18 years presenting to an ED with ILI from December 1, 2018, to November 30, 2019, was conducted. Data were analyzed March 23, 2020, to April 2, 2021. All children received a nasopharyngeal swab for RRP testing and were randomized 1:1 to the intervention group or control group (results not given, routine clinical care). Results were available in 45 minutes. Intention-to-treat analyses and modified intention-to-treat (clinician knows results) analyses were conducted using multivariable Poisson regression.

INTERVENTIONS

Rapid respiratory pathogen test results given to clinicians.

MAIN OUTCOMES AND MEASURES

Antibiotic prescribing was the primary outcome; influenza antiviral prescribing, ED length of stay, hospital admission, and recurrent health care visits were the secondary outcomes.

RESULTS

Among 931 ED visits (intervention group, 452 children group and control group, 456 children after exclusion of those not meeting criteria or protocol violations), a total of 795 RRP test results (85%) were positive. The median age of the children was 2.1 years (interquartile range, 0.9-5.6 years); 509 (56%) were boys. Most children (478 [53%]) were Hispanic, 688 children (76%) received government insurance, and 314 (35%) had a high-risk medical condition. In the intention-to-treat intervention group, children were more likely to receive antibiotics (relative risk [RR], 1.3; 95% CI, 1.0-1.7), with no significant differences in antiviral prescribing, medical visits, and hospitalization. In inverse propensity-weighted modified intention-to-treat analyses, children with test results known were more likely to receive antivirals (RR, 2.6; 95% CI, 1.6-4.5) and be hospitalized (RR, 1.8; 95% CI, 1.4-2.5); there was no significant difference in antibiotic prescribing (RR, 1.1; 95% CI, 0.9-1.4).

CONCLUSIONS AND RELEVANCE

The use of RRP testing in the ED for ILI did not decrease antibiotic prescribing in this randomized clinical trial. There is a limited role for RRP pathogen testing in children in this setting.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03756753.

Rapid Molecular Tests for Detecting Respiratory Pathogens Reduced the Use of Antibiotics in Children

Multiplex polymerase chain reaction (mPCR) is increasingly being used to diagnose infections caused by respiratory pathogens in pediatric inpatient facilities. mPCR assays detect a broader array of viruses, with higher specificity and sensitivity and faster turnaround than previous assays. We adapted the FilmArray Respiratory Panel (FA-RP) for diagnosing respiratory infections. FA-RP is an in vitro mPCR assay that simultaneously and rapidly (in about 1 h) detects 20 pathogens directly from respiratory specimens. Here, we studied the clinical efficacy of FA-RP in children who underwent testing for respiratory pathogens at Yeungnam University Hospital from November 2015 to August 2018. From November 2015 to June 2016, routine mPCR testing was performed on nasopharyngeal swabs using the routine mPCR kit. From November 2016 to July 2018, mPCR testing was performed using FA-RP. A total of 321 tests by routine mPCR and 594 tests by FA-RP were included. The positive detection rates for routine mPCR and FA-RP were 71.3% and 83.3%, respectively. FA-RP reduced the lead time, waiting time, turnaround time, intravenous (IV) antibiotic use, and length of hospital stay for pediatric patients. The decreased use of antibiotics is expected to reduce antibiotic resistance in children.

Viral causes of severe acute respiratory infection in hospitalized children and association with outcomes: A two-year prospective surveillance study in Suriname

BACKGROUND

Viruses are the most frequent cause of severe acute respiratory infection (SARI) in children. It is currently unknown whether presence of a virus, the number of viruses, or type of virus, are associated with clinical outcomes of pediatric SARI in developing countries.

METHODS

Between 2012 and 2014 nasopharyngeal swabs and demographic and clinical variables were prospectively collected for surveillance of viral causes of SARI in Surinamese children within 48 hours after hospitalization. These swabs were tested for 18 respiratory viruses using a multiplex polymerase chain reaction (PCR) panel to identify the specific viral causes of SARI, unknown to the treating physicians. In post hoc analyses we evaluated if the PCR results, and demographic and clinical characteristics, were associated with course of disease, duration of respiratory support, and length of stay (LOS).

RESULTS

Of a total of 316 analyzed children, 290 (92%) had one or more viruses. Rhinovirus/enterovirus (43%) and respiratory syncytial virus (34%) were most prevalent. Course of disease was mild in 234 (74%), moderate in 68 (22%), and severe in 14 (4%) children. Neither presence of a single virus, multiple viruses, or the type of virus, were different between groups. Prematurity and lower weight-for-age-z-score were independent predictors of a severe course of disease, longer duration of respiratory support, and longer LOS.

CONCLUSIONS

Viruses are common causes of pediatric SARI in Suriname, yet not necessarily associated with clinical outcomes. In developing countries, demographic and clinical variables can help to identify children at-risk for worse outcome, while PCR testing may be reserved to identify specific viruses, such as influenza, in specific patient groups or during outbreaks.

Rhinovirus: A Narrative Review on Its Genetic Characteristics, Pediatric Clinical Presentations, and Pathogenesis

Human rhinoviruses (HRVs) are the leading cause of common colds. With the development of new molecular methods since the 2000s, HRVs have been increasingly involved among severe clinical infections. Recent knowledge of the HRV genetic characteristics has also improved the understanding of their pathogenesis. This narrative review aims to provide a current comprehensive knowledge about this virus in the pediatric community. HRVs represent a main cause of upper and lower respiratory tract infections in children. HRV is the second virus involved in bronchiolitis and pneumonia in children, and HRV bronchiolitis has a higher risk of recurrent wheezing episode or asthma. Some recent findings described HRVs in stools, blood, or cerebrospinal fluid, thanks to new molecular techniques such as polymerase chain reaction (PCR) by detecting HRVs with high sensibility. However, the high rate of asymptomatic carriage and the prolonged excretion in postsymptomatic patients complicate interpretation. No sufficient data exist to avoid antibiotic therapy in pediatric high-risk population with HRV detection. Severe clinical presentations due to HRVs can be more frequent in specific population with chronic pathology or genetic particularity. Inflammatory response is mediated by the nuclear factor (NF)-kappa B pathway and production of interferon (IFN)-beta and IFN-gamma, interleukin 8 (IL8), and IL1b. No specific treatment or antiviral therapy exists, although research is still ongoing. Nowadays, in addition to benign diseases, HRVs are recognized to be involved in some severe clinical presentations. Recent advances in genetic knowledge or specific inflammatory response may lead to specific treatment.

Molecular Testing for Acute Respiratory Tract Infections: Clinical and Diagnostic Recommendations From the IDSA's Diagnostics Committee

The clinical signs and symptoms of acute respiratory tract infections (RTIs) are not pathogen specific. Highly sensitive and specific nucleic acid amplification tests have become the diagnostic reference standard for viruses, and translation of bacterial assays from basic research to routine clinical practice represents an exciting advance in respiratory medicine. Most recently, molecular diagnostics have played an essential role in the global health response to the novel coronavirus pandemic. How best to use newer molecular tests for RTI in combination with clinical judgment and traditional methods can be bewildering given the plethora of available assays and rapidly evolving technologies. Here, we summarize the current state of the art with respect to the diagnosis of viral and bacterial RTIs, provide a practical framework for diagnostic decision making using selected patient-centered vignettes, and make recommendations for future studies to advance the field.

Comparative epidemiology, hospital course, and outcomes of viral respiratory infections in hospitalized pediatric patients

PURPOSE

Acute respiratory illness is the leading cause of hospitalization for young children. Current guidelines recommend against testing to identify specific viruses due to a lack of data on the benefit of such testing. This study was designed to characterize epidemiology, hospital course, and outcomes of the various common virus -related hospitalization in children.

METHOD

Single-center retrospective chart review. All patients who had respiratory viral panel sent within 48 h of admission. Comparative demographic and outcome analysis. Statistical analysis using ANOVA and multivariable regression.

RESULT

1831 patients met the study criteria. Rhinovirus was the most common virus (55.9%). Coronavirus had the highest proportion of infants (61.2%), while influenza had the least (17.8%). Positive urine culture identified in 8.1% of patients, with blood and urine positivity at 2% each. Rhinovirus and parainfluenza were spread throughout the year, while Corona, RSV, and influenza were more predominant in winter months. Overall PICU admission rate 22.8% and was highest for RSV (28.0%) and lowest for adenovirus (13.5%). No difference in ICU length of stay among different virus. Intubation rate was 5.6% with a median duration of 5 days. Median hospital length of stay was 2 days and differ significantly with different virus (maximum four RSV and metapneumo virus). Mortality in the study population was 0.3%.

CONCLUSION

The difference in the disease course of different viruses may justify the resources required to test for the respiratory viral panel. This study data can serve as a benchmark for comparison of disease course of COVID-19 compared to other viral infections.

Impact of respiratory viral polymerase chain reaction testing on de-escalation of antibiotic therapy in children who require chronic positive pressure ventilation

BACKGROUND

Children who require chronic positive pressure ventilation (CPPV) are frequently hospitalized with acute respiratory infections. Although respiratory viral testing is often performed, it is unclear how positive results impact antibiotic use. We sought to assess the impact of respiratory viral testing on antibiotic use in hospitalized children on CPPV.

METHODS

This retrospective cohort study included hospitalized children on CPPV who had respiratory viral polymerase chain reaction (RVP) testing on admission. Primary exposure was a positive RVP result; primary outcome was antibiotic de-escalation, defined as discontinuation of antibiotics or narrowing of antimicrobial spectra. To determine the independent association of positive RVP and antibiotic de-escalation, a generalized linear mixed effect model was used to account for within patient clustering and confounders defined a priori (blood and respiratory cultures, leukocytosis, bandemia, chest radiograph findings, aspiration risk, and recent admission).

RESULTS

A total of 200 admissions representing 118 patients were included. A viral pathogen was identified in 46.5% (93/200) of admissions; rhinovirus was most frequently identified (61.5% of positive RVPs). Antibiotic de-escalation occurred in 33% of admissions (35.5% of RVP-positive admissions vs 30.8% of RVP-negative admissions; P = .49). In adjusted analysis, there was no association between positive RVP and antibiotics de-escalation (adjusted OR: 0.86; 95% confidence interval: 0.32-2.26).

CONCLUSION

This single center cohort study suggests that respiratory viral testing may not impact antibiotic prescribing for hospitalized children on CPPV. There is need for improved stewardship of both diagnostic testing and antimicrobial use in this population.

Clinical implications of aminotransferase elevation in hospitalised infants aged 8‐90 days with respiratory virus detection

Background

Methods

Results

Conclusions

Analysis of the impact of diagnostic virology tests on the use of antibiotics in paediatric inpatients with community-acquired pneumonia

Introduction

Viruses are one of the most common causes of community-acquired pneumonia (CAP) in children. Early identification of respiratory viruses could result in a decrease in the use of antibiotics.

Methods

Observational, retrospective study from January 2014 to June 2018, that included paediatric patients admitted with a diagnosis of CAP in a tertiary hospital, in which antigenic tests and/or viral PCR on a respiratory sample was performed.

Results

A total of 105 CAP episodes were included, with identification of a respiratory virus in 93 (88.6%) cases. Patients with respiratory syncytial virus (RSV) detection had a lower onset of empirical antibiotic therapy (35.1% vs. 55.9%, p-value = .042). In addition, cases with RSV or influenza identification required shorter duration of antibiotic therapy (receiving 45.6% ≥2 days vs. 68.8% of those not identified, p = .017).

Conclusion

The use of respiratory virus diagnostic techniques in our setting can optimise antibiotic use in children admitted with CAP.

Noninterruptive Clinical Decision Support Decreases Ordering of Respiratory Viral Panels during Influenza Season

OBJECTIVE

A growing body of evidence suggests that testing for influenza virus alone is more appropriate than multiplex respiratory viral panel (RVP) testing for general populations of patients with respiratory tract infections. We aimed to decrease the proportion of RVPs out of total respiratory viral testing ordered during influenza season.

METHODS

We implemented two consecutive interventions: reflex testing for RVPs only after a negative influenza test, and noninterruptive clinical decision support (CDS) including modifications of the computerized physician order entry search behavior and cost display. We conducted an interrupted time series of RVPs and influenza polymerase chain reaction tests pre- and postintervention, and performed a mixed-effects logistic regression analysis with a primary outcome of proportion of RVPs out of total respiratory viral tests. The primary predictor was the intervention period, and covariates included the provider, clinical setting, associated diagnoses, and influenza incidence.

RESULTS

From March 2013 to April 2019, there were 24,294 RVPs and 26,012 influenza tests (n = 50,306). Odds of ordering an RVP decreased during the reflex testing period (odds ratio: 0.432, 95% confidence interval: 0.397-0.469), and decreased more dramatically during the noninterruptive CDS period (odds ratio: 0.291, 95% confidence interval: 0.259-0.327).

DISCUSSION

The odds of ordering an RVP were 71% less with the noninterruptive CDS intervention, which projected 4,773 fewer RVPs compared with baseline. Assuming a cost equal to Medicare reimbursement rates for RVPs and influenza tests, this would generate an estimated averted cost of $1,259,474 per year.

CONCLUSION

Noninterruptive CDS interventions are effective in reducing unnecessary and expensive testing, and avoid typical pitfalls such as alert fatigue.

Predicting the microbial cause of community-acquired pneumonia: can physicians or a data-driven method differentiate viral from bacterial pneumonia at patient presentation?

BACKGROUND

Community-acquired pneumonia (CAP) requires urgent and specific antimicrobial therapy. However, the causal pathogen is typically unknown at the point when anti-infective therapeutics must be initiated. Physicians synthesize information from diverse data streams to make appropriate decisions. Artificial intelligence (AI) excels at finding complex relationships in large volumes of data. We aimed to evaluate the abilities of experienced physicians and AI to answer this question at patient admission: is it a viral or a bacterial pneumonia?

METHODS

We included patients hospitalized for CAP and recorded all data available in the first 3-h period of care (clinical, biological and radiological information). For this proof-of-concept investigation, we decided to study only CAP caused by a singular and identified pathogen. We built a machine learning model prediction using all collected data. Finally, an independent validation set of samples was used to test the pathogen prediction performance of: (i) a panel of three experts and (ii) the AI algorithm. Both were blinded regarding the final microbial diagnosis. Positive likelihood ratio (LR) values > 10 and negative LR values < 0.1 were considered clinically relevant.

RESULTS

We included 153 patients with CAP (70.6% men; 62 [51-73] years old; mean SAPSII, 37 [27-47]), 37% had viral pneumonia, 24% had bacterial pneumonia, 20% had a co-infection and 19% had no identified respiratory pathogen. We performed the analysis on 93 patients as co-pathogen and no-pathogen cases were excluded. The discriminant abilities of the AI approach were low to moderate (LR+ = 2.12 for viral and 6.29 for bacterial pneumonia), and the discriminant abilities of the experts were very low to low (LR+ = 3.81 for viral and 1.89 for bacterial pneumonia).

CONCLUSION

Neither experts nor an AI algorithm can predict the microbial etiology of CAP within the first hours of hospitalization when there is an urgent need to define the anti-infective therapeutic strategy.

Association between multiple respiratory viral infections and pediatric intensive care unit admission among infants with bronchiolitis

Background

It is unclear whether multiple respiratory viral infections are associated with more severe bronchiolitis requiring pediatric intensive care unit (PICU) admission. We aimed to identify the association between multiple respiratory viral infections and PICU admission among infants with bronchiolitis.

Methods

We performed a 1:1 case-control study enrolling previously healthy full-term infants (≤12 months) with bronchiolitis admitted to the PICU as cases and those to the general pediatric ward as controls from 2015 to 2017. Multiplex polymerase chain reaction (PCR) was used for detection of the respiratory viruses. We summarized the characteristics of infants admitted to the PICU and the general pediatric unit. Multivariable logistic regression analysis was used to fit the association between multiple respiratory viral infections (≥2 strains) and PICU admission.

Results

A total of 135 infants admitted to the PICU were compared with 135 randomly selected control infants admitted to the general pediatric unit. The PICU patients were younger (median: 2.2 months, interquartile range: 1.3–4.2) than the general ward patients (median: 3.2 months, interquartile range: 1.6–6.4). Respiratory syncytial virus (74.1%), rhinovirus (28.9%), and coronavirus (5.9%) were the most common viruses for bronchiolitis requiring PICU admission. Patients with bronchiolitis admitted to the PICU tended to have multiple viral infections compared with patients on the general ward (23.0% vs. 10.4%, P < 0.001). In the multivariable logistic regression analysis, bronchiolitis with multiple viral infections was associated with higher odds of PICU admission (adjusted odds ratio: 2.56, 95% confidence interval: 1.17–5.57, P = 0.02).

Conclusion

Infants with multiviral bronchiolitis have higher odds of PICU admission compared with those with a single or nondetectable viral infection.

Analysis of the impact of diagnostic virology tests on the use of antibiotics in paediatric inpatients with community-acquired pneumonia

Introducción

Los virus son una de las causas más frecuentes de neumonía adquirida en la comunidad (NAC) en niños. La identificación precoz de virus respiratorios podría suponer una disminución en el consumo de antibióticos.

Métodos

Estudio observacional, retrospectivo, desde enero del 2014 hasta junio del 2018, que incluyó a los pacientes pediátricos ingresados en un hospital terciario con diagnóstico de NAC, a los que se realizó test antigénico o PCR viral en muestra respiratoria.

Resultados

Se incluyeron 105 episodios de NAC, identificándose algún virus respiratorio en 93 (88,6%) casos. Los pacientes con detección de virus respiratorio sincitial (VRS) presentaron menor inicio de antibioterapia empírica (35,1% vs. 55,9%, p valor: 0,042). Además, los casos con identificación de VRS o influenza precisaron menor duración de antibioterapia (recibiendo el 45,6% ≥ 2 días frente al 68,8% de los que no se identificó, p = 0,017).

Conclusión

El uso de técnicas diagnósticas de virus respiratorios en nuestro medio puede optimizar el consumo de antibióticos en niños ingresados con NAC.

Cost-Effective Respiratory Virus Testing

The timely and accurate diagnosis of respiratory virus infections has the potential to optimize downstream (posttesting) use of limited health care resources, including antibiotics, antivirals, ancillary testing, and inpatient and emergency department beds. Cost-effective algorithms for respiratory virus testing must take into consideration numerous factors, including which patients should be tested, what testing should be performed (for example, antigen testing versus reverse transcription-PCR testing or influenza A/B testing versus testing with a comprehensive respiratory virus panel), and the turnaround time necessary to achieve the desired posttesting outcomes. Despite the clinical impact of respiratory virus infections, the cost-effectiveness of respiratory virus testing is incompletely understood. In this article, we review the literature pertaining to the cost-effectiveness of respiratory virus testing in pediatric and adult patient populations, in emergency department, outpatient, and inpatient clinical settings. Furthermore, we consider the cost-effectiveness of a variety of testing methods, including rapid antigen tests, direct fluorescent antibody assays, and nucleic acid amplification tests.

Multiplex Platforms for the Identification of Respiratory Pathogens: Are They Useful in Pediatric Clinical Practice?

Respiratory tract infections (RTIs) are extremely common especially in the first year of life. Knowledge of the etiology of a RTI is essential to facilitate the appropriate management and the implementation of the most effective control measures. This perspective explains why laboratory methods that can identify pathogens in respiratory secretions have been developed over the course of many years. High-complexity multiplex panel assays that can simultaneously detect up to 20 viruses and up to four bacteria within a few hours have been marketed. However, are these platforms actually useful in pediatric clinical practice? In this manuscript, we showed that these platforms appear to be particularly important for epidemiological studies and clinical research. On the contrary, their routine use in pediatric clinical practice remains debatable. They can be used only in the hospital as they require specific equipment and laboratory technicians with considerable knowledge, training, and experience. Moreover, despite more sensitive and specific than other tests routinely used for respiratory pathogen identification, they do not offer significantly advantage for detection of the true etiology of a respiratory disease. Furthermore, knowledge of which virus is the cause of a respiratory disease is not useful from a therapeutic point of view unless influenza virus or respiratory syncytial virus are the infecting agents as effective drugs are available only for these pathogens. On the other hand, multiplex platforms can be justified in the presence of severe clinical manifestations, and in immunocompromised patients for whom specific treatment option can be available, particularly when they can be used simultaneously with platforms that allow identification of antimicrobial resistance to commonly used drugs. It is highly likely that these platforms, particularly those with high sensitivity and specificity and with low turnaround time, will become essential when new drugs effective and safe against most of the respiratory viruses will be available. Further studies on how to differentiate carriers from patients with true disease, as well as studies on the implications of coinfections and identification of antimicrobial resistance, are warranted.

Treatment, outcomes and costs of asthma exacerbations in Chilean children: a prospective multicenter observational study

OBJECTIVE

To describe potential regional variations in therapies for severe asthma exacerbations in Chilean children and estimate the associated health expenditures.

METHODS

Observational prospective cohort study in 14 hospitals over a one-year period. Children five years of age or older were eligible for inclusion. Days with oxygen supply and pharmacological treatments received were recorded from the clinical chart. A basic asthma hospitalization basket was defined in order to estimate the average hospitalization cost for a single patient. Six months after discharge, new visits to the Emergency Room (ER), use of systemic corticosteroids and adherence to the controller treatment were evaluated.

RESULTS

396 patients were enrolled. Patients from the public health system and from the north zone received significantly more days of oxygen, systemic corticosteroids and antibiotics. Great heterogeneity in antibiotic use among the participating hospitals was found, from 0 to 92.3% (ICC 0.34, 95% CI 0.16-0.52). The use of aminophylline, magnesium sulfate and ketamine varied from 0 to 36.4% between the different Pediatric Intensive Care Units (ICC 0.353, 95% CI 0.010-0.608). The average cost per inpatient was of $1910 USD. 290 patients (73.2%) completed the follow-up six months after discharge. 76 patients (26.2%) were not receiving any controller treatment and nearly a fourth had new ER visits and use of systemic corticosteroids due to new asthma exacerbations.

CONCLUSIONS

Considerable practice variation in asthma exacerbations treatment was found among the participating hospitals, highlighting the poor outcome of many patients after hospital discharge, with an important health cost.

A Study of the Use and Outcomes From Respiratory Viral Testing at a Mid-Sized Children's Hospital

This study was a retrospective analysis of inpatient and emergency department (ED) data on respiratory pathogen panel (RPP) testing between December 16, 2013, and December 15, 2015, at a mid-sized children's hospital. We assessed whether RPP decreases antibiotic days of therapy and length of hospital stay for pediatric patients with acute respiratory infections. In the inpatient population, patients testing positive with RPP were given fewer antibiotic days of therapy (2.99 vs 4.30 days; P = .032) and had shorter hospital stays (2.84 vs 3.80 days; P = .055) than patients testing negative. In the ED population, patients testing positive with RPP received fewer discharge prescriptions for antibiotics than patients not tested (8.8% vs 41.1%; P < .001). RPP use was more prevalent in admitted patients than in ED patients (78.9% vs 7.3%; P < .001). Our results suggest that RPP testing curbs antibiotic use and decreases length of hospital stay.

Viral respiratory infections diagnosed by multiplex polymerase chain reaction in pediatric patients

Syndromic diagnosis by multiplex nucleic acid amplification tests is the most practical approach to respiratory tract infections since the symptoms are rarely agent‐specific. The aim of this study was to investigate the respiratory viruses in children admitted to a university hospital with acute respiratory tract infection during the last 8 years by a multiplex polymerase chain reaction (PCR) assay. A total of 3162 respiratory samples collected from children between April 2011 and April 2018 tested by a multiplex real‐time PCR assay. Two different commercial assays were used during the study period, "AusDiagnostics/Respiratory Pathogens 12 (AusDiagnostics)" used between April 2011 and December 2015, which changed to "Fast Track Diagnostics/Respiratory Pathogens 21 (Fast Track Diagnostics)" after January 2016 to cover more viruses. Nucleic acid extraction was done by EZ1 Advanced XL platform (QIAGEN). Respiratory pathogens detected in 1857 of the 3162 (58.7%) samples. The most prevalent viruses during the 8‐year period were rhinovirus/enterovirus (RV/EV; 36.2%), respiratory syncytial virus (RSV; 19%), and influenza virus A/B (14.7%). Rhinovirus was the main contributor to the RV/EV group as shown by the assay used during the 2016‐2018 period. RV/EV and adenoviruses detected throughout the year. Influenza virus was most frequently detected during January to March when both RSV and metapneumovirus were also in circulation. The coinfection percentage was 10.2%. Rhinovirus was the most common virus in coinfections while RSV plus rhinovirus/enterovirus were the most frequent combination. RSV and metapneumovirus showed a similar seasonal distribution to the influenza virus, which made it necessary to use a virological diagnostic assay during the influenza season.

Evaluation of national guidelines for bronchiolitis: AGREEments and controversies

AIM

Bronchiolitis is a common respiratory illness and is a leading cause of hospitalisation in infancy. We aimed to appraise three recent national bronchiolitis guidelines produced by the Australasian Paediatric Research in Emergency Departments International Collaborative, the National Institute for Health and Care Excellence in the UK and the American Academy of Pediatrics.

METHODS

A group of final-year medical students and one senior clinician used the AGREE II tool to appraise each guideline in two stages. First, two students appraised each guideline independently and presented their results. Second, two self-selected students met with the senior clinicians to review all scores to ensure completeness of the appraisal and consistency of AGREE II application.

RESULTS

The guidelines scored well overall, with particular strengths in the domains of clarity of presentation, scope and purpose and rigour of development. Comparison of the recommendations across each guideline demonstrated a high degree of consistency. Notable differences included recommendations for the role of palivizumab in prevention of bronchiolitis, the use of continuous pulse oximetry monitoring in the hospitalised patient and the value of respiratory virus testing.

CONCLUSIONS

Our appraisal of bronchiolitis guidelines from three high-income countries demonstrated that they were of high quality, with substantial areas of agreement. Most aspects of clinical practice should be uniform for this common paediatric condition. Areas of guideline weakness were in the domains of applicability and editorial independence. We identified three areas of controversy where further research is needed to support stronger evidence-based recommendations.

Impact of multiplex molecular assay turn-around-time on antibiotic utilization and clinical management of hospitalized children with acute respiratory tract infections

BACKGROUND

Empiric antibiotic treatment is common among children with acute respiratory tract infections (ARTI), despite infections being predominately viral. The use of molecular respiratory panel assays has become increasingly common for medical care of patients with ARTIs.

STUDY DESIGN

This was a 6-year retrospective, single-centered study of pediatric inpatients who tested positive for an ARTI respiratory pathogen. We examined the relationship between clinical outcomes and whether the patient was tested using the Luminex Respiratory Viral Panel ([RVP]; in-use: Dec. 2009 - Jul. 2012) or Biofire Respiratory Pathogen Panel ([RP]; in-use Aug. 2012 - Jun. 2016). The prevalence and duration of pre-test empiric antibiotics, post-test oseltamivir administration to influenza patients, chest x-rays and length of stay between the two assays was compared.

RESULTS

A total of 5142 patients (1264 RVP; 3878 RP) were included. The median laboratory turn-around-time for RP was significantly shorter than RVP (1.4 vs. 27.1 h, respectively; p < .001). Patients tested with RP were less likely to receive empiric antibiotics (OR: 0.45; p < .001; 95% CI: 0.39, 0.52) and had a shorter duration of empiric broad-spectrum antibiotics (6.4 h vs. 32.9 h; p < .001) compared to RVP patients. RP influenza patients had increased oseltamivir use post- test compared to RVP influenza patients (OR: 13.56; p < .001; 95% CI: 7.29, 25.20).

CONCLUSIONS

Rapid molecular testing positively impacts patient management of ARTIs. Adopting assays with a shorter turn-around-time improves decision making by decreasing empirical antibiotic use and duration, decreasing chest x-rays, increasing timely oseltamivir administration, and reducing length of stay.

Clinical impact of rapid molecular detection of respiratory pathogens in patients with acute respiratory infection

•

Diagnosis with FilmArray-RP was associated with changes in medical management.

•

Accurate and rapid diagnosis decreased antibiotic use and complementary studies, and improved oseltamivir use.

•

The multiplex PCR respiratory panel permitted a high viral detection rate not only in children but in adults.

Background

Acute respiratory infections (ARI) are a leading cause of morbidity and mortality worldwide. There is a need to demonstrate the clinical impact of using the new, rapid and sensitive molecular assays in prospectively designed studies.

Objectives

To study the impact on medical management of a rapid molecular assay in patients with respiratory infections.

Study design

A prospective, randomized, non-blinded study was performed in patients presenting to the Emergency Department during two respiratory seasons (2016–2017). Diagnosis was performed by FilmArray Respiratory Panel (FilmArray-RP) or by immunofluorescence assay (IFA).

Results

A total of 432 patients (156 children and 276 adults) were analyzed. Diagnosis with FilmArray-RP was associated with significant changes in medical management including withholding antibiotic prescriptions (OR:15.52, 95%CI:1.99–120.83 in adults and OR:12.23, 95%CI:1.56–96.09 in children), and reduction in complementary studies in children (OR:9.64, 95%CI:2.13–43.63) compared to IFA. Decrease in oseltamivir prescriptions was significantly higher in adults in the FilmArray-RP group (p = 0.042; OR:1.19, 95%CI:0.51-2.79) compared to adults managed with IFA. Diagnostic yield was significantly higher by FilmArray-RP (81%) than by IFA (31%)(p < 0.001). The median time from sample collection to reporting was 1 h 52 min by FilmArray-RP and 26 h by IFA (p < 0.001).

Conclusions

The high respiratory viruses’ detection rate and availability of results within two hours when using FilmArray-RP were associated with decreases in antibiotic prescriptions and complementary studies and more accurate use of oseltamivir.

Association between semi-quantitative microbial load and respiratory symptoms among Thai military recruits: a prospective cohort study

BACKGROUND

Multiplex real-time polymerase chain reaction assays have improved diagnostic sensitivity for a wide range of pathogens. However, co-detection of multiple agents and bacterial colonization make it difficult to distinguish between asymptomatic infection or illness aetiology. We assessed whether semi-quantitative microbial load data can differentiate between symptomatic and asymptomatic states for common respiratory pathogens.

METHODS

We obtained throat and nasal swab samples from military trainees at two Thai Army barracks. Specimens were collected at the start and end of 10-week training periods (non-acute samples), and from individuals who developed upper respiratory tract infection during training (acute samples). We analysed the samples using a commercial multiplex respiratory panel comprising 33 bacterial, viral and fungal targets. We used random effects tobit models to compare cycle threshold (Ct) value distributions from non-acute and acute samples.

RESULTS

We analysed 341 non-acute and 145 acute swab samples from 274 participants. Haemophilus influenzae type B was the most commonly detected microbe (77.4% of non-acute and 64.8% of acute samples). In acute samples, nine specific microbe pairs were detected more frequently than expected by chance. Regression models indicated significantly lower microbial load in non-acute relative to acute samples for H. influenzae non-type B, Streptococcus pneumoniae and rhinovirus, although it was not possible to identify a Ct-value threshold indicating causal etiology for any of these organisms.

CONCLUSIONS

Semi-quantitative measures of microbial concentration did not reliably differentiate between illness and asymptomatic colonization, suggesting that clinical symptoms may not always be directly related to microbial load for common respiratory infections.

Multicenter evaluation of the Alere™ i influenza A&B assay using respiratory specimens collected in viral transport media

Rapid and accurate detection of influenza virus is critical for proper patient management. The Alere™ i Influenza A&B assay is an isothermal nucleic acid amplification test capable of detecting influenza A and B viruses directly from respiratory specimens. In this multicenter clinical trial conducted in the US, we evaluated the clinical performance of the Alere™ i Influenza A&B assay against that of the Prodesse ProFlu+ assay. A total of 1243 fresh, leftover nasal or nasopharyngeal swabs eluted in viral transport medium were tested by both assays. Sensitivity and specificity of the Alere™ i Influenza A&B assay were 97.8% (95% CI 94.6-99.2) and 96.6% (95% CI 95.2-97.5) for influenza A and 92.9% (95% CI 85.5-96.9) and 98.3% (95% CI 97.4-98.0) for influenza B. The Alere™ i Influenza A&B assay is an ideal molecular assay for influenza virus detection due to its high sensitivity and specificity with minimal hands-on and turn-around-time.

Clinical and laboratory profiles of hospitalized children with acute respiratory virus infection

Purpose

Despite the availability of molecular methods, identification of the causative virus in children with acute respiratory infections (ARIs) has proven difficult as the same viruses are often detected in asymptomatic children.

Methods

Multiplex reverse transcription polymerase chain reaction assays were performed to detect 15 common respiratory viruses in children under 15 years of age who were hospitalized with ARI between January 2013 and December 2015. Viral epidemiology and clinical profiles of single virus infections were evaluated.

Results

Of 3,505 patients, viruses were identified in 2,424 (69.1%), with the assay revealing a single virus in 1,747 cases (49.8%). While major pathogens in single virus-positive cases differed according to age, human rhinovirus (hRV) was common in patients of all ages. Respiratory syncytial virus (RSV), influenza virus (IF), and human metapneumovirus (hMPV) were found to be seasonal pathogens, appearing from fall through winter and spring, whereas hRV and adenovirus (AdV) were detected in every season. Patients with ARIs caused by RSV and hRV were frequently afebrile and more commonly had wheezing compared with patients with other viral ARIs. Neutrophil-dominant inflammation was observed in ARIs caused by IF, AdV, and hRV, whereas lymphocyte-dominant inflammation was observed with RSV A, parainfluenza virus, and hMPV. Monocytosis was common with RSV and AdV, whereas eosinophilia was observed with hRV.

Conclusion

In combination with viral identification, recognition of virus-specific clinical and laboratory patterns will expand our understanding of the epidemiology of viral ARIs and help us to establish more efficient therapeutic and preventive strategies.

More Pathogenicity or Just More Pathogens?-On the Interpretation Problem of Multiple Pathogen Detections with Diagnostic Multiplex Assays

Modern molecular diagnostic approaches in the diagnostic microbiological laboratory like real-time quantitative polymerase chain reaction (qPCR) have led to a considerable increase of diagnostic sensitivity. They usually outperform the diagnostic sensitivity of culture-based approaches. Culture-based diagnostics were found to be insufficiently sensitive for the assessment of the composition of biofilms in chronic wounds and poorly standardized for screenings for enteric colonization with multi-drug resistant bacteria. However, the increased sensitivity of qPCR causes interpretative challenges regarding the attribution of etiological relevance to individual pathogen species in case of multiple detections of facultative pathogenic microorganisms in primarily non-sterile sample materials. This is particularly the case in high-endemicity settings, where continuous exposition to respective microorganisms leads to immunological adaptation and semi-resistance while considerable disease would result in case of exposition of a non-adapted population. While biofilms in chronic wounds show higher pathogenic potential in case of multi-species composition, detection of multiple pathogens in respiratory samples is much more difficult to interpret and asymptomatic enteric colonization with facultative pathogenic microorganisms is frequently observed in high endemicity settings. For respiratory samples and stool samples, cycle-threshold-value-based semi-quantitative interpretation of qPCR results has been suggested. Etiological relevance is assumed if cycle-threshold values are low, suggesting high pathogen loads. Although the procedure is challenged by lacking standardization and methodical issues, first evaluations have led to promising results. Future studies should aim at generally acceptable quantitative cut-off values to allow discrimination of asymptomatic colonization from clinically relevant infection.

Short-term relevance of lower respiratory viral coinfection in inpatients under 2 years of age

Introduction

Advances in molecular diagnosis have made it possible to detect previously unknown viral agents as causative agents of lower respiratory tract infections (LRTI). The frequency and relevance of viral coinfections is still debatable.

Objective

Compare clinical presentation and severity between single virus infection and viral coinfection in children admitted for LRTI.

Methods

A 3-year period observational study (2012–2015) included children younger than two years admitted for LRTI. Viral identification was performed using PCR technique for 16 viruses. Clinical data and use of health resources was gathered during hospital stay using a standard collection form and we compared single virus infection and viral coinfections.

Results

The study included 524 samples (451 patients); 448 (85.5%) had at least one virus identified. Viral coinfections were found in 159 (35.5%). RSV and HRV were the most commonly identified virus; bronchiolitis and pneumonia the most frequent diagnosis. Patients with viral coinfections were older, attended day-care centers, had previous recurrent wheezing more frequently and were more symptomatic at admission. These patients did not have more complementary exams performed but were prescribed medications more often. Viral coinfection group did not show longer length of hospital stay and oxygen need, more need for ICU nor ventilatory support.

Discussion

Our study showed a significant proportion of viral coinfections in young infants admitted with LRTI and confirmed previous data showing that prescription was more frequent in inpatients with viral coinfections, without an association with worst clinical outcome.

[Short-term relevance of lower respiratory viral coinfection in inpatients under 2 years of age]

INTRODUCTION

Advances in molecular diagnosis have made it possible to detect previously unknown viral agents as causative agents of lower respiratory tract infections (LRTI). The frequency and relevance of viral coinfections is still debatable.

OBJECTIVE

compare clinical presentation and severity between single virus infection and viral coinfection in children admitted for LRTI.

METHODS

A 3-year period observational study (2012-2015) included children younger than two years admitted for LRTI. Viral identification was performed using PCR technique for 16 viruses. Clinical data and use of health resources was gathered during hospital stay using a standard collection form and we compared single virus infection and viral coinfections.

RESULTS

The study included 524 samples (451 patients); 448 (85,5%) had at least one virus identified. Viral coinfections were found in 159 (35,5%). RSV and HRV were the most commonly identified virus; bronchiolitis and pneumonia the most frequent diagnosis. Patients with viral coinfections were older, attended day-care centers, had previous recurrent wheezing more frequently and were more symptomatic at admission. These patients did not have more complementary exams performed but were prescribed medications more often. Viral coinfection group did not show longer length of hospital stay and oxygen need, more need for ICU nor ventilatory support.

DISCUSSION

Our study showed a significant proportion of viral coinfections in young infants admitted with LRTI and confirmed previous data showing that prescription was more frequent in inpatients with viral coinfections, without an association with worst clinical outcome.

Impact of viral multiplex real-time PCR on management of respiratory tract infection: a retrospective cohort study

Background

Significance and clinical utility of multiple virus detection by multiplex real-time polymerase chain reaction (rtPCR) in respiratory tract infection remain unclear.

Methods

This retrospective cohort study analyzed how virus detection affected clinical management. During a 27-month period, clinical and laboratory information was collected from all children and adults in two Swiss tertiary centres whose respiratory samples were tested for respiratory viruses with a 16-plex rtPCR test.

Results

Pathogens were identified in 140 of 254 patients (55%); of those patients, there was ≥1 virus in 91 (65%), ≥ 1 bacterium in 53 (38%), and ≥1 virus and bacterium in 11 (8%). Of 80 patients with viral infection, 59 (74%) received antibiotics. Virus detection was associated with discontinuation of antibiotics in 2 of 20 adults (10%) and 6 of 14 children (43%). Overall 12 adults (34%) and 18 children (67%) were managed correctly without antibiotics after virus detection (p = 0.01). When taking biomarkers, radiologic presentations, and antibiotic pre-treatment into account, the impact of rtPCR and appropriateness of therapy for clinically viral infections increased to 100% in children and 62% in adults.

Conclusions

A substantial reduction of unnecessary antibiotic prescriptions seems possible. Appropriate application of rtPCR results in respiratory tract infections should be encouraged.

Pitfalls in interpretation of CT-values of RT-PCR in children with acute respiratory tract infections

Background

The relation between viral load and disease severity in childhood acute respiratory tract infections (ARI) is not fully understood.

Objectives

To assess the clinical relevance of the relation between viral load, determined by cycle threshold (CT) value of real-time reverse transcription-polymerase chain reaction assays and disease severity in children with single- and multiple viral ARI.

Study design

582 children with ARI were prospectively followed and tested for 15 viruses. Correlations were calculated between CT values and clinical parameters.

Results

In single viral ARI, statistically significant correlations were found between viral loads of Respiratory Syncytial Virus (RSV) and hospitalization and between viral loads of Human Coronavirus (HCoV) and a disease severity score. In multiple-viral ARI, statistically significant correlations between viral load and clinical parameters were found. In RSV-Rhinovirus (RV) multiple infections, a low viral load of RV was correlated with a high length of hospital stay and a high duration of extra oxygen use. The mean CT value for RV, HCoV and Parainfluenza virus was significantly lower in single- versus multiple infections.

Conclusion

Although correlations between CT values and clinical parameters in patients with single and multiple viral infection were found, the clinical importance of these findings is limited because individual differences in host-, viral and laboratory factors complicate the interpretation of statistically significant findings. In multiple infections, viral load cannot be used to differentiate between disease causing virus and innocent bystanders.

Interventions to improve antibiotic prescribing practices for hospital inpatients

BACKGROUND

Antibiotic resistance is a major public health problem. Infections caused by multidrug-resistant bacteria are associated with prolonged hospital stay and death compared with infections caused by susceptible bacteria. Appropriate antibiotic use in hospitals should ensure effective treatment of patients with infection and reduce unnecessary prescriptions. We updated this systematic review to evaluate the impact of interventions to improve antibiotic prescribing to hospital inpatients.

OBJECTIVES

To estimate the effectiveness and safety of interventions to improve antibiotic prescribing to hospital inpatients and to investigate the effect of two intervention functions: restriction and enablement.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library), MEDLINE, and Embase. We searched for additional studies using the bibliographies of included articles and personal files. The last search from which records were evaluated and any studies identified incorporated into the review was January 2015.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and non-randomised studies (NRS). We included three non-randomised study designs to measure behavioural and clinical outcomes and analyse variation in the effects: non- randomised trials (NRT), controlled before-after (CBA) studies and interrupted time series (ITS) studies. For this update we also included three additional NRS designs (case control, cohort, and qualitative studies) to identify unintended consequences. Interventions included any professional or structural interventions as defined by the Cochrane Effective Practice and Organisation of Care Group. We defined restriction as 'using rules to reduce the opportunity to engage in the target behaviour (or increase the target behaviour by reducing the opportunity to engage in competing behaviours)'. We defined enablement as 'increasing means/reducing barriers to increase capability or opportunity'. The main comparison was between intervention and no intervention.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data and assessed study risk of bias. We performed meta-analysis and meta-regression of RCTs and meta-regression of ITS studies. We classified behaviour change functions for all interventions in the review, including those studies in the previously published versions. We analysed dichotomous data with a risk difference (RD). We assessed certainty of evidence with GRADE criteria.

MAIN RESULTS

This review includes 221 studies (58 RCTs, and 163 NRS). Most studies were from North America (96) or Europe (87). The remaining studies were from Asia (19), South America (8), Australia (8), and the East Asia (3). Although 62% of RCTs were at a high risk of bias, the results for the main review outcomes were similar when we restricted the analysis to studies at low risk of bias.More hospital inpatients were treated according to antibiotic prescribing policy with the intervention compared with no intervention based on 29 RCTs of predominantly enablement interventions (RD 15%, 95% confidence interval (CI) 14% to 16%; 23,394 participants; high-certainty evidence). This represents an increase from 43% to 58% .There were high levels of heterogeneity of effect size but the direction consistently favoured intervention.The duration of antibiotic treatment decreased by 1.95 days (95% CI 2.22 to 1.67; 14 RCTs; 3318 participants; high-certainty evidence) from 11.0 days. Information from non-randomised studies showed interventions to be associated with improvement in prescribing according to antibiotic policy in routine clinical practice, with 70% of interventions being hospital-wide compared with 31% for RCTs. The risk of death was similar between intervention and control groups (11% in both arms), indicating that antibiotic use can likely be reduced without adversely affecting mortality (RD 0%, 95% CI -1% to 0%; 28 RCTs; 15,827 participants; moderate-certainty evidence). Antibiotic stewardship interventions probably reduce length of stay by 1.12 days (95% CI 0.7 to 1.54 days; 15 RCTs; 3834 participants; moderate-certainty evidence). One RCT and six NRS raised concerns that restrictive interventions may lead to delay in treatment and negative professional culture because of breakdown in communication and trust between infection specialists and clinical teams (low-certainty evidence).Both enablement and restriction were independently associated with increased compliance with antibiotic policies, and enablement enhanced the effect of restrictive interventions (high-certainty evidence). Enabling interventions that included feedback were probably more effective than those that did not (moderate-certainty evidence).There was very low-certainty evidence about the effect of the interventions on reducing Clostridium difficile infections (median -48.6%, interquartile range -80.7% to -19.2%; 7 studies). This was also the case for resistant gram-negative bacteria (median -12.9%, interquartile range -35.3% to 25.2%; 11 studies) and resistant gram-positive bacteria (median -19.3%, interquartile range -50.1% to +23.1%; 9 studies). There was too much variance in microbial outcomes to reliably assess the effect of change in antibiotic use. Heterogeneity of intervention effect on prescribing outcomesWe analysed effect modifiers in 29 RCTs and 91 ITS studies. Enablement and restriction were independently associated with a larger effect size (high-certainty evidence). Feedback was included in 4 (17%) of 23 RCTs and 20 (47%) of 43 ITS studies of enabling interventions and was associated with greater intervention effect. Enablement was included in 13 (45%) of 29 ITS studies with restrictive interventions and enhanced intervention effect.

AUTHORS' CONCLUSIONS

We found high-certainty evidence that interventions are effective in increasing compliance with antibiotic policy and reducing duration of antibiotic treatment. Lower use of antibiotics probably does not increase mortality and likely reduces length of stay. Additional trials comparing antibiotic stewardship with no intervention are unlikely to change our conclusions. Enablement consistently increased the effect of interventions, including those with a restrictive component. Although feedback further increased intervention effect, it was used in only a minority of enabling interventions. Interventions were successful in safely reducing unnecessary antibiotic use in hospitals, despite the fact that the majority did not use the most effective behaviour change techniques. Consequently, effective dissemination of our findings could have considerable health service and policy impact. Future research should instead focus on targeting treatment and assessing other measures of patient safety, assess different stewardship interventions, and explore the barriers and facilitators to implementation. More research is required on unintended consequences of restrictive interventions.

Assessment of the Usefulness of Multiplex Real-Time PCR Tests in the Diagnostic and Therapeutic Process of Pneumonia in Hospitalized Children: A Single-Center Experience

The aim of the study was assessment of the usefulness of multiplex real-time PCR tests in the diagnostic and therapeutic process in children hospitalized due to pneumonia and burdened with comorbidities. Methods. The study group included 97 children hospitalized due to pneumonia at the Karol Jonscher Teaching Hospital in Poznań, in whom multiplex real-time PCR tests (FTD respiratory pathogens 33; fast-track diagnostics) were used. Results. Positive test results of the test were achieved in 74 patients (76.3%). The average age in the group was 56 months. Viruses were detected in 61 samples (82% of all positive results); bacterial factors were found in 29 samples (39% of all positive results). The presence of comorbidities was established in 90 children (92.78%). On the basis of the obtained results, 5 groups of patients were established: viral etiology of infection, 34 patients; bacterial etiology, 7 patients; mixed etiology, 23 patients; pneumocystis, 9 patients; and no etiology diagnosed, 24 patients. Conclusions. Our analysis demonstrated that the participation of viruses in causing severe lung infections is significant in children with comorbidities. Multiplex real-time PCR tests proved to be more useful in establishing the etiology of pneumonia in hospitalized children than the traditional microbiological examinations.

Single- and multiple viral respiratory infections in children: disease and management cannot be related to a specific pathogen

Background

The number of viral pathogens associated with pediatric acute respiratory tract infection (ARI) has grown since the introduction of reverse transcription real-time polymerase chain reaction (RT-PCR) assays. Multiple viruses are detected during a single ARI episode in approximately a quarter of all cases. The clinical relevance of these multiple detections is unclear, as is the role of the individual virus. We therefore investigated the correlation between clinical data and RT-PCR results in children with single- and multiple viral ARI.

Methods

Data from children with ARI were prospectively collected during two winter seasons. RT-PCR testing for 15 viruses was performed in 560 ARI episodes. In the patients with a single-viral etiology, clinical data, laboratory findings, patient management- and outcome data were compared between the different viruses. With this information, we compared data from children of whom RT-PCR data were negative, with children with single- and multiple viral positive results.

Results

The viral detection rate was 457/560 (81.6%) of which 331/560 (59.1%) were single infections and 126/560 (22.5%) were multiple infections. In single viral infections, some statistically significant differences in demographics, clinical findings, disease severity and outcome were found between children with different viral etiologies. However, no clinically recognizable pattern was established to be virus-specific. In a multivariate analysis, the only variables that were correlated with longer hospital stay were the use of oxygen and nebulizer therapy, irrespective of the viral pathogen. Children with RT-PCR positive test results had a significant higher disease severity, fever, length of hospital stay, days of extra oxygen supply, and days of antibiotic treatment than children with a negative RT-PCR test result. For children with single- versus children with multiple positive RT-PCR test results, these differences were not significant.

Conclusions

Disease (severity), management and outcome in pediatric ARI are not associated with a specific virus. Single- and multiple viral ARI do not significantly differ with regard to clinical outcome and patient management. For general pediatrics, RT-PCR assays should be restricted to pathogens for which therapy is available or otherwise may have clinical consequences. Further research with an extended panel of RT-PCR assays and a larger number of inclusions is necessary to further validate our findings.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-2118-6) contains supplementary material, which is available to authorized users.

Impact of a Transition from Respiratory Virus Shell Vial to Multiplex PCR on Clinical Outcomes and Cost in Hospitalized Children

While respiratory virus PCR panel (RVPP) is more expensive than shell vial (SV) cell culture, it has been shown to reduce unnecessary diagnostic procedures, decrease the inappropriate use of antimicrobials, and shorten the hospital length of stay (LOS). We therefore hypothesized that, for hospitalized children, RVPP would be associated with improved clinical outcomes but higher hospital charges than SV cell culture. We performed a retrospective cohort study of hospitalized children. Multivariate analysis was performed, and p-values were calculated. Respiratory virus testing was collected in a total of 1625 inpatient encounters, of which 156 were tested positive by RVPP (57.7%) and 112 were tested positive by SV (11.1%, p < 0.05). Excluding human rhinovirus (HRV) and human metapneumovirus (hMPV) from the analysis, patients with a positive test from SV had more comorbidities (p = 0.04) and higher mortality (p = 0.008). Patients with a positive test from RVPP had shorter LOS (p = 0.0503). Hospital charges for patients with a positive test from RVPP were lower, but not significantly so. When a multivariate analysis was performed, there were no statistically significant differences in comorbidities, mortality, LOS, or median hospital charges between those patients with a positive SV and those with a positive RVPP. Although testing with RVPP significantly increased the detection of respiratory viruses, clinical outcomes remained comparable to those tested with SV, however RVPP was found to not be associated with higher long-term hospital costs.

The role of the NxTAG® respiratory pathogen panel assay and other multiplex platforms in clinical practice

INTRODUCTION

The advent of nucleic acid amplification tests has significantly improved the aetiologic diagnosis of respiratory infections. However, multiplex real-time polymerase chain reaction (PCR) can be technologically challenging. Areas covered: This paper reports the results of the main published studies on the NxTAG Respiratory Pathogen Panel (RPP) and discusses the advantages and disadvantages of extensive use of multiplex assays in clinical practice. Expert commentary: Currently available data seem to indicate that routine use of multiplex assays, including NxTAG RPP Assay, should be recommended only when epidemiological data concerning circulation of viruses and bacteria have to be collected. Their use in clinical practice seems debatable. They have limited sensitivity and specificity at least in the identification of some infectious agents or, as in the case of NxTAG RPP, they have not been evaluated in a sufficient number of patients to allow definitive conclusions. In the future, the clinical relevance of multiplex assays, including NxTAG RPP, could significantly increase, mainly because a number of new antiviral agents effective against several respiratory viruses for which no drug is presently available will be marketed. In addition, it is highly likely that the efficiency of multiplex assays will be significantly improved.